//============================================================================
//
//  This file is part of GPSTk, the GPS Toolkit.
//
//  The GPSTk is free software; you can redistribute it and/or modify
//  it under the terms of the GNU Lesser General Public License as published
//  by the Free Software Foundation; either version 3.0 of the License, or
//  any later version.
//
//  The GPSTk is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with GPSTk; if not, write to the Free Software Foundation,
//  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
//
//  Copyright 2004, The University of Texas at Austin
//  Dagoberto Salazar - gAGE ( http://www.gage.es ). 2008, 2009, 2011
//
//============================================================================

//============================================================================
//
//This software developed by Applied Research Laboratories at the University of
//Texas at Austin, under contract to an agency or agencies within the U.S.
//Department of Defense. The U.S. Government retains all rights to use,
//duplicate, distribute, disclose, or release this software.
//
//Pursuant to DoD Directive 523024
//
// DISTRIBUTION STATEMENT A: This software has been approved for public
//                           release, distribution is unlimited.
//
//=============================================================================

/**
 * @file SatArcMarker.hpp
 * This class keeps track of satellite arcs caused by cycle slips.
 */

#ifndef GPSTK_SATARCMARKER_HPP
#define GPSTK_SATARCMARKER_HPP

#include "../gpstk/ProcessingClass.hpp"



namespace gpstk
{

/** @addtogroup GPSsolutions */
//@{


/** This class keeps track of satellite arcs caused by cycle slips.
 *
 * This class is meant to be used with the GNSS data structures objects
 * found in "DataStructures" class.
 *
 * A typical way to use this class follows:
 *
 * @code
 *   RinexObsStream rin("ebre0300.02o");
 *
 *   gnssRinex gRin;
 *   LICSDetector markCSLI;
 *   SatArcMarker markArc;
 *
 *   while(rin >> gRin)
 *   {
 *      gRin >> markCSLI >> markArc;
 *   }
 * @endcode
 *
 * The "SatArcMarker" object will visit every satellite in the GNSS
 * data structure that is "gRin" and, if a cycle slip has happened
 * (indicated by the corresponding CS flag), it will increase the
 * value of the corresponding "TypeID::satArc" type.
 *
 * By default, the "SatArcMarker" objects will only watch the
 * "TypeID::CSL1" cycle slip flag. This may be changed, although it is
 * rarely necessary because CS detectors raise all flags when a cycle
 * slip happens.
 *
 * An important feature of "SatArcMarker" objects is that you can
 * set a period after arc change when the affected satellite will be
 * considered "unstable". By default, unstable period is set to 31 s,
 * but it may be changed using the appropriate constructor or using
 * the "setUnstablePeriod()" method.
 *
 * Likewise, SatArcMarker" objects are also able to delete unstable
 * satellites from GDS. This feature is disabled by default, but may
 * be activated using the appropriate constructor or using the
 * "setDeleteUnstableSats()".
 *
 * \warning Be aware that this class DOES NOT apply cycle slip detection
 * algorithms, so you MUST invoke CS detection objects BEFORE calling
 * SatArcMarker objects.
 *
 * \warning Objects in this class store their internal state, so you
 * MUST NOT use the SAME object to process DIFFERENT data streams.
 *
 * @sa LICSDetector.hpp and MWCSDetector.hpp for CS detection classes.
 *
 */
class SatArcMarker : public ProcessingClass
{
public:

    /// Default constructor. It will only watch "TypeID::CSL1" flag.
    SatArcMarker()
        : watchCSFlag(TypeID::CSL1), deleteUnstableSats(false),
          unstablePeriod(31.0)
    { };


    /** Common constructor
     *
     * @param watchFlag        Cycle slip flag to be watched.
     * @param delUnstableSats  Whether unstable satellites will be deleted.
     * @param unstableTime     Number of seconds since last arc change
     *                         that a satellite will be considered as
     *                         unstable.
     */
    SatArcMarker( const TypeID& watchFlag,
                  const bool delUnstableSats,
                  const double unstableTime );


    /// Method to get the default CS flag type being used.
    virtual TypeID getCSFlag() const
    {
        return watchCSFlag;
    };


    /** Method to set the default CS flag type to be used.
     *
     * @param watchFlag     Cycle slip flag to be watched.
     */
    virtual SatArcMarker& setCSFlag(const TypeID& watchFlag)
    {
        watchCSFlag = watchFlag;
        return (*this);
    };


    /// Method to known if unstable satellites will be deleted.
    virtual bool getDeleteUnstableSat() const
    {
        return deleteUnstableSats;
    };


    /** Method to set if unstable satellites will be deleted.
     *
     * @param delUnstableSats  Whether unstable satellites will be deleted.
     */
    virtual SatArcMarker& setDeleteUnstableSats(const bool delUnstableSats)
    {
        deleteUnstableSats = delUnstableSats;
        return (*this);
    };


    /// Method to get the number of seconds since last arc change that a
    /// satellite will be considered as unstable.
    virtual double getUnstablePeriod() const
    {
        return unstablePeriod;
    };


    /** Method to set the number of seconds since last arc change that a
     *  satellite will be considered as unstable.
     *
     * @param unstableTime     Number of seconds since last arc change
     *                         that a satellite will be considered as
     *                         unstable.
     */
    virtual SatArcMarker& setUnstablePeriod(const double unstableTime);


    /** Method to get the arc changed epoch.
     * @param sat              Interested SatID.
     */
    virtual CommonTime getArcChangedEpoch(const SatID& sat);

    /** Returns a satTypeValueMap object, adding the new data generated
     *  when calling this object.
     *
     * @param epoch     Time of observations.
     * @param gData     Data object holding the data.
     */
    virtual satTypeValueMap& Process( const CommonTime& epoch,
                                      satTypeValueMap& gData )
    throw(ProcessingException);


    /** Returns a gnnsSatTypeValue object, adding the new data generated
     *  when calling this object.
     *
     * @param gData    Data object holding the data.
     */
    virtual gnssSatTypeValue& Process(gnssSatTypeValue& gData)
    throw(ProcessingException);


    /** Returns a gnnsRinex object, adding the new data generated when
     *  calling this object.
     *
     * @param gData    Data object holding the data.
     */
    virtual gnssRinex& Process(gnssRinex& gData)
    throw(ProcessingException);


    /// Returns a string identifying this object.
    virtual std::string getClassName(void) const;


    /// Destructor
    virtual ~SatArcMarker() {};


private:


    /// Cycle slip flag to be watched.
    TypeID watchCSFlag;


    /// Flag indicating if unstable satellites will be deleted.
    bool deleteUnstableSats;


    /// Number of seconds since arc change that a satellite will be
    /// considered as unstable.
    double unstablePeriod;


    /// Map holding information regarding every satellite
    std::map<SatID, double> satArcMap;


    /// Map holding information about epoch of last arc change
    std::map<SatID, CommonTime> satArcChangeMap;


    /// Map keeping track if this satellite is new or not
    std::map<SatID, bool> satIsNewMap;


}; // End of class 'SatArcMarker'

//@}

}  // End of namespace gpstk

#endif   // GPSTK_SATARCMARKER_HPP
